Regulatory B cells (Bregs) are a subset of B cells with immunomodulatory effects. The study of Bregs began with a variety of animal models of immune diseases. Studies in patients with autoimmune diseases have further clarified that Bregs are a group of immune cells that secrete inhibitory cytokines such as interleukin-10. Abnormal functions and numbers of Bregs have been found in a variety of autoimmune diseases. The study of the negative immune regulatory network involving Bregs is expected to provide new therapeutic ideas for diseases such as immune diseases, cancer, infection and inflammation. Starting from the discovery and immune regulation mechanism of Bregs, this paper focuses on its regulatory mechanism and clinical research value in the occurrence and development of autoimmune diseases, tumors, infectious diseases and inflammation.
ObjectiveTo systematically review the efficacy of double autologous hematopoietic stem cell transplantation (ASCT) in newly diagnosed multiple myeloma (NDMM). Methods PubMed, EMbase, The Cochrane Library, CNKI, and WanFang Data databases were electronically searched to collect randomized controlled trials (RCTs) on double ASCT for NDMM from inception to February 2021. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Meta-analysis was then performed by RevMan 5.3 software. Results A total of 6 RCTs involving 2 226 NDMM patients were included. The results of meta-analysis indicated that compared with single ASCT, more patients who received double ASCT could achieve satisfactory partial response (VGPR) or better (RR=1.12, 95%CI 1.01 to 1.25, P=0.03). Double ASCT resulted in a higher progression-free survival (PFS) rate from the second year for high-risk patients (2-year: RR=0.49, 95%CI 0.28 to 0.86, P=0.01; 5-year: HR=0.61, 95%CI 0.43 to 0.85, P=0.004). There were no statistical differences in treatment-related mortality and 5-year overall survival between the two groups. ConclusionsCompared with single ASCT, double ASCT can improve the VGPR rate of NDMM patients and the PFS rate of high-risk patients with comparable toxicities. Due to limited quality and quantity of the included studies, more high-quality studies are needed to verify the above conclusions.